An Electromagnetic Refining Apparatus with Conductive Excitation of Current in Liquid Metal

Abstract

The electromagnetic processes in an apparatus for electromagnetically refining aluminum melt with conduction excitation of current in the melt are simulated. The numerical calculation is carried out using the Maxwell finite element software package. Based on numerical calculations, the equivalent circuit parameters and the main electromagnetic characteristics of the apparatus are determined. From the distribution of bulk electromagnetic forces in the melt, the terminal velocities for particles of different diameters are obtained. It is shown that the operating voltages are in the range from 0.1 to 6.0 V depending on the current and contact resistance values. The preheating of metal in the trough by conductive supply of electricity in the system under study can only be used jointly with another kind of heating. With the operating currents in the secondary circuit higher that 2000 A, the terminal velocities of particles 30—50 m in diameter are in the range 1—4 mm/s. This means that efficient removal of impurity particles with a diameter of 30 m or larger can be achieved in the apparatus under study. With the secondary circuit current less than 1500 A, the particle migration direction is governed by the buoyancy force, which also governs the (inefficient) natural particle sedimentation process.